The investigation of the nature of this disase appears to be quite overlooked or neglected. It seems indeed a remarkable circumstance that a malady which annually destroys many thousand trees, and which possesses very distinct and marked characteristics - as many believe - should have its very existence doubted by some of our most eminent nomologists, who regard the death of the trees as merely the result Of neglected cultivation and want of fertility m the soil.

Our attention has been just called to this subject by a letter from Salmon Lyman, of Manchester, Conn., who writes, - " The Yellows in peach trees is becoming very common among the trees in Connecticut, and unless something can be done to arrest the disease, people will become discouraged in trying to raise them. It was introduced into this vicinity with trees from New-Jersey. I am informed that the yellows does not exist within many miles of your place. I observe that you cultivate Crawford's Early and Late Me-locoton - these varieties, with some others, I have supposed did not exist in a healthy state, and that they were originally propagated in New-Jersey from diseased stock, and that, remove them where you would, the native taint would develop itself in the yellows. I have procured Crawford's Early from New-Jersey, Long-Island, Newburgh, Providence, and Boston, and not one of all lived more than from three to eight years before they were worthless from disease. I have never seen a Crawford peach tree that appeared to be more than eight or nine years old, which did not show decided marks of disease.

Have you trees of these New-Jersey sorts which are more than eight or ten years old? If so, what can be the influencee that prevents the developement of the yellows? It cannot be your lime and ashes, for they are treated in New-Jersey with an abundance of lime and marl.

"I am surprised that so little is said about the yellows in the Horticultural papers, and penological conventions. Would not the history of its rise and introduction into the different sections of our country, be interesting, and lead to the proper means for guarding against its introduction in new sections of the country? I believe there was but little of it in this part of Connecticut, until the Moras Multicaulis speculation, which was taken to New-Jersey in exchange for peach trees, which could be sold here at twice their cost. They were brought here in large quantities, peddled out or sold at auction, and wherever they were planted the yellows now prevails".

In reply to the preceding inquiry, we may state, that we have never observed any symptom of the yellows on a single tree of the Crawford in Western New-York; but as those observed were mostly not over eight or nine years old, we applied for further information to H. E. Hooker, of Rochester, a very careful and intelligent observer of fruit trees and their maladies, and he has furnished the following statement: - . "The oldest trees of Crawford's Early Melocoton, with which I am acquainted, are standing in Mr. Schenck's orchard, a very extensive market cultivator of the peach, near Rochester, N. Y. They have been in full bearing for near seven years, under my own observation, and were large trees when I first knew them; they must be at least twelve or fifteen years from the bud; and neither now or ever have shown any symptoms of the Yellows, as I understand that disease. I have never been able to discover a tree in all Mr. Schenck's orchards, nor among the other smaller orchards around us, which were set with trees from him, and which he procured in New-Jersey, where the peach tree in the orchard is not expected to survive more than four or five crops of fruit.

Crawford's Late, has not been in bearing for so long a time, but I have seen no indications of disease in this any more than in the former, as a variety; in fact, we have considered it a peculiarly hardy sort.

" The Yellows, as I understand it, is a disease whose symptoms are, a very slender, feeble growth of young wood, with small yellow sickly looking foliage, a feeble starved appearance of the tree, and generally a crop of slendry yellow shoots appearing along the large branches; which symptoms increase for two or more years before death ensues. I have seen this, in some orchards brought from New-Jersey, and observed the premature ripening of the fruit, and spread of the disease until the orchard nearly or quite disappeared) and as I thought took with them some heretofore sound trees, which grew in their vicinity. I confidently looked for the spread of the evil, and was prepared to blame the man who had brought us trees from the infected district. But I am not satisfied that it does not spread here, nor that there is no one diseased tree (having the yellows,) within my knowledge in Rochester.

" These facts, have quite staggered my faith in the "diseased stock " theory, and lead me rather to believe, that the poor shallow soil, from which the peach tree rapidly exhausts the elements of growth and fruitfulness, under a system of heavy cropping without much manure, rather than the presence of any poison or virus in the system, has been the cause of so much complaint of premature death of the peach tree in the eastern and southern States. I am not clear that the apple trees of New-Jersey, in the peach districts are not similarly affected, and should judge that a removal of them to Western New-York, would increase their size and prolong their days, in the same proportion that the health and duration of peach trees grown in New-Jersey nurseries is prolonged, by removing them to our deeper and richer soil.

" It would be an interesting experiment, if some one in the east would try peach trees in Western New-York, along side of some from New-Jersey, and let the public know the results. Here trees from both sections usually do equally well, so far as my observation extends; a/etc exceptions, as I have said, have come under my notice".

Our chief object in furnishing these statements, is to invite investigation. There is no question, but that much of the soil in Western New-York, is one of the best that the peach can grow in - where we have seen those that measured a foot in diameter, and which were probably more than forty years old, bearing fruit. Nevertheless, we have witnessed there the prevalence of the yellows in a virulent form, and decidedly contagious in its character, among the most vigorous trees. All the usual symptoms of premature ripening, and discolored and insipid flesh, followed by sickly leaves, and wiry shoots from the large branches, first made their appearance on trees introduced from New-Jersey; the next year after the first appearance of these symptoms, all the trees standing nearest to them were observed to be similarly affected, but at first on the branches nearest the diseased tree. By a prompt removal of those affected, the malady was checked, and it is now many years since the la6t vestige has departed from this region. A further proof of its contagious character, is the fact that a knife used in cutting a diseased tree, communicated the poison to another; and a bud from one that had scarcely showed an appearance of decline, proved fatal to the tree in which it was inserted.

That this malady may prove more contagious at certain times or under certain circumstances, is by no means improbable. That the soil has a large influence in its prevention, was confirmed by the fact, that in the neighborhood of Burlington, as Thomas Hancock informed us, there are flourishing trees some thirty years old, on a favorable locality, while in other places they never survive but a comparatively short period. But the soil cannot be all, for an intelligent cultivator residing on the Hudson, at a place where the peach trees are commonly quite short lived, informs us that trees procured where this disease is unknown, grow and flourish for a much longer period than those from an infected region.